Mixing and kneading machine and process



A. P. LUHMANN.

MIXING AND KN EADING MACHINE AND PROCESS.

APPLICATION FILED, AUG. 16, 1919.

1,406,666, Patented Feb. 14, 1922.

4 SHEETSSHEET 1.

. Inventor By I4 AttorneyA A. P. LOHMANN. MIXING ANDWT-KNEADING MACHINE AND PROCESS.

APPLICATION FILED AUG-16,1919.

Patented Feb. 14, 1922.

4 SHEETS-SHEET Z- By A ttorneyd A. P. LOHMANN.

MIXING AND KNEADING MACHINE AND PROCESS.

APPLICATION FILED AUG-16117919.

1,406,666, Patented Feb. 14, 1922.

4 SHEETS-SH EET 3 A. P. .LOHMANN.

MIXING AND KNEADING MACHINE AND PROCESS. APPLICATION FILED AUG-16,1919.

1 ,406,666, Patented Feb. 14, 1922.

'4 SHEETS-SHEET 4.

I Inventor By Attorney/0 UNITED STATES PATENT OFFICE.

ALFRED P. LOHMANN, OF AKRON, OHIO.

MIXING AND KN'EADING MACHINE AND PROCESS.

Specification of Letters Patent.

Patented Feb. 14, 1922.

T 0 all whom it may concern:

Be it known that I, ALFRED P. LOHMANN, a citizen of the United States, and a resident of Akron, in the county of Summit and State of Ohio, have invented certain new and useful Improvements in Mixing and Kneading Machines and Processes, of which the following'is a description.

The general object of my invention is to provide for the mixing and kneading of the material in a more thorough, eflicient, and uniform manner, with an accompanying reduction in both the power and labor costs and time of operation, as compared with machines and processes now employed for this purpose.

The most commonly used type of machine for mixing materials such as rubber or other gums with the various pigments or other materials with which it is desired to combine them, is the so-called mixing mill. This mixing mill comprises, in general, two adjacent, parallel cylinders adapted to revolve in opposite angular directions at different peripheral velocities. The material to be mixed is placed into or near the bite of these two cylinders, and by reason of the difi'erence in peripheral velocities, there results a smearing action along the line of contact between the two cylinders which operates to mix more or less intimately the various component materials. However, in these mills the line ofsmearing contact is limited to the length of the cylinders. Also, there is no effective provision for longitudinal travel of the ingredients, their only longitudinal movement being accomplished by merely the haphazard and occasional manual shifting of portions of the material from one end of the mill to the other by the operator.

Among the specific objects of my invention are, the extension of the line of smearing contact of the mill to effect a more thorough smearing action, and the provision of means for continuously and automatically conveying the ingredients longitudinally substantially from end to end of the machine to effect a more uniform intermingling than has been heretofore possible,

In the accompanying drawings,

Fig. 1 is a perspective view of one form of my improved machine.

. Fig. 2 is a side elevation thereof, partly broken away.

Figs. 3 and 4 are detail views partly in cross-section, of one form of my material supplying cartridge.

Figs. 5, 6 and 7 are side elevations of three different types of mixing members which I may employ.

Fig. 6- is a transverse sectional view on the lines 66 of Fig. 6.

Figs. 8 and 9 are cross sectional views of the members shown in Figs. 5 and 6, respectively, and Fig. 10 is an end elevation of the member shown in Fig. 7.

Fig. 11 is a side elevation of a still different form of mixing member, and Fig. 12 is a development, on a slightly reduced scale, of the periphery of the member shown in Fig. 11.

Mountedin a suitable frame 11 (Figs. 1 and 2) is the mixing chamber 12. This chamber may be of any desired form, but as here illustrated it is cylindrical.

The mixing member 13 is revolubly mounted Within the chamber 12, and may be rotated by any suitable power transmitting means, such as the gear G. The member 13 is provided, as shown more clearly in Figs. 5, 6 and 7, with a plurality of helically arranged blades or flanges. In each instance, the helix of one of the blades, as 14, is righthanded when viewed from the lower or left end of the member 13, and the helix of another blade, such as 15, is left-handed, when so viewed. It will be noted, also, that there is a gap 16 between the right-hand end of the blade 14', and the right-hand end' of the blade 15, and a similar gap 17 between the left-hand end of blade 15 and the left-hand end of blade 14:. The result of the above described arrangement of blades is that as the mixing member rotates within the mixing chamber, one of the blades, say blade 14,

-will convey the material from one (in this casethe left-hand) end of the chamber substantially to the opposite end of the cham-' ber, whence the material will pass through the gap 16 and be conveyed by the blade 15, substantially to its starting point. It will then pass through the gap 17 and repeat the cycle again and again until the batch of material is removed from the machine.

The above described operation serves to commingle the component materials uniformly, but in order to effect a more intimate mixture, I have provided each of the blades 14, 15, with a smearing surface, 14:", 15", in addition to its conve ing surface 14", 15*. These smearing sur aces may be integral with the blades, as shown, or may be separable, and may be smooth or serrated as found most desirable. As clearly shown in the drawing, the conveying surfaces of the blades are so shaped as to not unduly force the material outwardly against the inner wall or surface of the chamber, their primary function being, by virtue of their helical longitudinal arrangement, to convey the material longitudinally. However, it is obvious that a certain amount of the material will constantly find its way between these smearing surfaces and the inner surface of the chammat rials are mixed together with great thoroughness.

As shown in Fig. (5 the ends of the blades adjacent the end walls of the mixing chamber may be spiral, with the result that they remove from these walls any material which may have a tendency to adhere thereto and assist in reversing the flow of material in. its travel to the opposite end of the cylinder.

Referring particularly to Figs. 1 and 2, the mixing chamber 12 may be heated or cooled by any suitable means, as by a steam or water'jacket 19, which surrounds the mixing chamber, and is supplied with steam or water from any suitable source such as the pipes indicated at 20. The interior of the mixing member may be similarly heated or cooled if desired.

Hinged at 21 within the frame 11', isthe access door 22 of the mixing chamber. Any suitable means may be employed for hinging this door, but preferably the hinge is so constructed as to leave a blade or interrupter such as 21 within the cylinder. The purpose of the blade is to break up any tendency which may exist for the same material to idly revolve with the rotor during successive rotations thereof. This door 22 when open occupies the position shown in full lines in Fig. 1, and in dotted lines in Fig. A. cover 23 may also be provided and, as here shown, hinged to the frame 11 at 24. Any suitable means may be employed for elevating the door 22, such, for example, as the fluid pressure devices indicated at 25, which are connected to the lower door 22,'by a flexible connector 26. Instead of arranging these fluid pressure devices as shown, a single device of this character may be applied to the bottom of the door 22 at its center, to push this door closed. The cover 23 may be opened and closed manually or in any other desired manner.

The door 22 may be provided with means for retaining a drum or similar container for supplyin certain ingredients to the materials in ,t e mixing chamber during the mixing operation. vFor this urpose, employ the members 27, 28, which are revoluly mounted and capable of limited longitudinal movement in the bosses 29, 30, at opposite ends of the door 22. As indicated in Figs. 1, 3 and 4, the inner ends of these members are screw threaded, and their outer ends are provided with hand wheels or similar devices such as shown at 31, 32, to facilitate their manual manipulation.

A drum which I may use to advantage in this connection com rises a hollow cylindrical shell 33 provided at each end with an end piece or closure 34. A pin 35 formed upon one of the inwardly extending prongs 36 of the end piece co-operates with a U- shaped slot 37 in the end of the shell, to keep the end. piece in the desired position. The end piece 34 is provided with a female screw 38 to receive the screw threaded end of the member 28. The end piece for the other end of the drum is like the end piece 34. The female screw 38 iii one or both of the end pieces 34 is preferably locatezl ofi center, so as to give the drum the agi ated motion of a tumbling barrel. As shown in Fig. 1, I referably provide upon the frame 11, an id er pulley 39, which guides a suit ably driven chain, with which the sprocket id keyed to the member 27, is adapted to cooperate when the door 22 is closed, to rotate the drum 33. Any other desired form of drive, such as friction disks, may be substituted for the chain and sprocket drive here shown.

It may here be pointed out that an important feature of the material supplying means just described is its portability. It may be filled and closed at any desired source of supply and then transported to the mixing machine. It is not again opened until it is withinthe mixing machine, as will presently appear. This feature is particularly advantageous when the material to be supplied is of a dusty, disagreeable or unhygienic nature and it is desired to guard the operatives from contact with it.

' in operation, some of the materials to be mixed are placed in the mixing chamber.

The drum is filled with certain other ingredients such as pigments or other desired material which it is desired to mix with the materials in the mixing chamber, and the end pieces are held in closed position by the pin 35 resting in the inner extremity of the slot 36, as shown in Fig. 4-. The drum'is then placed in the door 22, the screw threaded ends of the members 27, 28, being screwed iar lto the drum ends 34, as also shown in ower is now applied to the gear G, to drive the mixing member 13, and the fluid operated device is actuated to raise the door 22. This door may not be completely closed at first due to the interference of a large amount of material in the mixing chamber. However, continued rotation of the mixing member will so readjust the position of the material within the chamber that the lower door will be permitted to close completely. The cover is then closed, and if desired it may be arranged so that when closed it locks the door 22 in position, as shown in the full lines in Fig. 2. This, however, is not essential, and the cover may be eliminated-entirely, without affecting the efficient operation of the mixer.

The sprocket 40 now rotates the drum 33,

and as a result of this rotation the shell of the drum is moved circumferentially with respect to the end pieces so that the pin 35 rests in the inner end of the longitudinal portion of the slot 37, as shown at 35, Fig. 4:. Whenever it is desired to introduce the material contained in the drum into the mixingchamber, the members 27, 28, are pulled outwardly, thus pullin the end pieces into the position shown in ig. 3. The gaps thus left between the ends of the shell and the end pieces provide an outlet through which the material is sifted into the mixing chamber as the drum rotates. The tumbling barrel action resulting from the oflt'center mounting of the drum accelerates the egress of the material therefrom.

' The action of the rotating mixing member 13 upon the component materials'is as above described. Th s action may be continued as long as is necessary to effect the desired mixing or kneading of the material.

The cover and door of the chamber are then again opened and the mixed material is removed;

The modified form of mixing. member shown in ig. 11 is found preferable, under certain circumstances, to any of those above described. In this modified form, I have indicated the blades by the letters A,

. B, C and D. The blades A and D terminate 6, for example, and the intermediate blades B, C, are provided for extending the longitudinal movement of the material initiated by the blades A, B.

The operation of this modified construction will be more readily understood by referring to Fig. 12, which shows a development of its surface. Let us first trace the movement of the material which we find being conveyed by the blade D. As the member rot-ates, this material is conveyed from the top of' the left-hand end of blade D (top of Fig. 12) to the blade B. Thence it is conveyed to the right, to substantially the right-hand end of the cylinder where it passes through port B D-. Passing'through this port part of it will go through the smaller port B C onto the blade C, and part through the smaller port C D onto the blade D again.

That portion of the material that has passed through B C will now be conveyed by blade C to substantially the left-hand end onto blade A, which will in turn convey it.

through port C A onto blade C again.

Thus it is apparent that the material is not only moved substantially from end to end of the cylinder and subjected to the effective smearing action heretofore described in connection with the other forms of mixing members, but it is also repeatedly divided and subdivided in a manner which in certain instances adds materially to the effecti-veness of the mixing.

It is obvious from the above that no skilled labor is required in the operation of my machine. The exact amount of each of the component materials for each batch to be mixed is, of course, determined in advance. It can also be,predetermined how long the mixing operation should be continued before and after the material from the drum is introduced into the chamber. All that the operator has to do is to supply the measured quantities of material, start the machine in motion, open. the drum at a predetermined "time, and finally stop the machine at another predetermined time-and remove the mixed material. In other words, the personal equation is entirely eliminated, and not only is each batch of material mixed to the desired degree of thoroughness, but each batch is exactly like every other batch. product is obtained.

The terms and expressions which I have employed are used as terms of description and not of limitation, and I have no inten tion, in the use of such terms and expres- SlOIlS, of excluding any mechanical equivalents of the features shown and-described,

Thus a uniformly homogeneous or portions thereof, but recognize that various structural modifications are possible within the scope of the invention claimed.

Vhat I claim is:

1. The method of. mixing and kneading materials which consists in propelling the materials continually and alternately from end to end of a confining space, and simultaneously imparting to the materials move ment about the periphery of said space.

2. The method of mixing and kneading materials which consists in propelling the materials continuously and alternately from end to end of a confining space, and simultaneously imparting to the material a smearing action.

3. A device for mixing materials comprising a container and means located therein for propelling the materials continuously and alternately from end to end of said container. and simultaneously imparting to the material movement about the periphery of said container.

4. A device for mixing materials comprising a container and means located therein for propelling the materials continuously and alternately from end to end of said container and simultaneously imparting to the material a smearing action between said means and the inner peripheral surface of said container.

5. A device for mixing materials comprising a container and means located therein and forming with said container a confined space, said means being constructed and arranged to propel the materials continuously and alternately from end to end of the container Within said confined space, and simultaneously to impart to the material movement about the periphery of said container.

6. In a machine for mixing and kneading materials, the combination of a substantially cylindrical mixing chamber, and a relatively rotary member located therein, said chamber and member being adapted, by their relative rotation, to propel said materials continuously and alternately from end to end of said chamber and simultaneously'to impart to the materials circumferential movement about the inner peripheral sur face of said chamber.

7. ln a machine for mixing and kneading materials, the combination of a substantially cylindrical mixing chamber and a relatively rotary member located therein and comprising an axial body portion provided with a right hand helical flange and aleft hand helical flange. said flanges beginning at opposite ends of the chamber and extending substantially to the end opposite that of beginning and extending also throughout their length uninterruptedly from said body portion substantially to the inner cylindrical surface of the chamber, whereby said material is conveyed continuously and alternately from end to end of the chamber.

8. In a machine for mixing and kneading materials, the combination of a substantially cylindrical mixing chamber and a relatively rotary member located therein and comprising an axial body portion provided with a right hand helical flange and a left hand helical flange, said flanges beginning at opposite ends of the chamber and extending substantially to the end opposite that of beginning and extending also throughout their lengthnninterruptedly from said body portion substantially to the inner cylindrical surface of the chamber, whereby said material is conveyed continuously and alternately from end to end of the chamber, said flanges terminating in scrapers for the end walls of the chamber.

9. In a machine for mixing and kneading materials, the combination of a substantially cylindrical mixing chamber and a relatively rotary member located therein and comprising an axial body portion provided with a right hand helical flange and a left hand helical flange. said flanges beginning at opposite ends of the chamber and extending substantially to the end opposite that of beginning and extending also throughout their length uninterruptedly from said body portion substantially to the inner cylindrical surface of the chamber, whereby said ma terial is conveyed continuously and alternately from end to end of the chamber, said body port-ion being provided also with one or more additional flanges intermediate said first mentioned flanges. I

10. In a machine for mixinga-nd kneading materials, the combination of a substantially cylindrical mixing chamber anfl a. relatively rotary member located therein and comprising an axial body portion provided with aright hand helical flange and a left hand helical fiange,'said flanges beginning at opposite ends of the chamber and extending with substantially a one-half turn substantially to the end opposite that of beginning and extending also throu hout their length uninterruptedly from said body portion substantially to the inner cylindrical surface of the chamber, whereby said material is conveyed continuously and alternately from end to end of said chamber. 7

11. Ina machine for mixing and kneading materials. the combination of a substantially cylindrical mixing chamber and a relatively rotary member located therein and comprising an axial body portion provided with a right hand helical flange and a left hand helical flange, said flanges beginning at opposite ends of the chamber and extending substantially to the end opposite that of beginning and extendin also throughout their length uninterruptedi y from said body portion to the inner cylindrical surface of the chamber, each of said flanges being provided with aconveying surface and with a smearing surface adjacent the inner cylindrical surface of the chamber. whereby said material is conveyed continuously and alter.-

nately from end to end of the chamber and 'multaneously smeared against said inner surface.

1-2. In a machine for mixing and kneading materials, a mixing chamber, a swinging 10 ALFRED P. LOHMANN.

to said machine when said door is 15 

